The invention discloses a method and device for salvaging a drilling bit, and relates to the technical field of bored pile construction. When a drilling bit disengages, whether the disengaging drilling bit is in the vertical direction or not is judged through the condition that the bottom end of a drill pipe makes contact with the disengaging drilling bit; when the drilling bit is not in the vertical direction, and the disengaging drilling bit has a large inclination angle, the inclination angle and the coordinates of a central hole of the drilling bit are determined first, then a drilling bitsalvaging device is arranged on the lower part of the drill pipe of a drilling rig in an inclined mode, the drill pipe is drilled down by the drilling rig, the drilling bit salvaging device is directly inserted into the central hole of the drilling bit, and an inverted tooth structure of the drilling bit salvaging device is connected with an inner thread of the central hole of the drilling bit ina clamping mode, so that the drilling bit can be salvaged timely and quickly, and the difficult problem of salvaging of existing drilling bits is solved.